<html>

<style>

    .ballon {
        width: 150px;
        height: 200px;
        background: url("./imgs/1111.jpg");
        background-size: 150px 200px;
        -webkit-animation-name: scaleDraw; /*关键帧名称*/
        -webkit-animation-timing-function: ease-in-out; /*动画的速度曲线*/
        -webkit-animation-iteration-count: infinite; /*动画播放的次数*/
        -webkit-animation-duration: 5s; /*动画所花费的时间*/
    }

    @keyframes scaleDraw { /*定义关键帧、scaleDrew是需要绑定到选择器的关键帧名称*/
        0% {
            transform: scale(1); /*开始为原始大小*/
        }
        25% {
            transform: scale(1.1); /*放大1.1倍*/
        }
        50% {
            transform: scale(1);
        }
        75% {
            transform: scale(1.1);
        }
    }
</style>
<body>
<div class="ballon"></div>
</body>
</html>